[PATCH v4] Add basic address decoding support for Marvell 370/XP
thomas.petazzoni at free-electrons.com
Thu Sep 20 01:18:22 EDT 2012
Do you have any comments on this patch series? It has received a:
Acked-by: Arnd Bergmann <arnd at arndb.de>
with the only comment being the missing DT binding documentation. And
therefore wanted to see if you had other comments about the patches
before I send a v5 that includes the requested DT binding documentation.
On Tue, 11 Sep 2012 14:27:13 +0200, Thomas Petazzoni wrote:
> Andrew, Jason, Grégory,
> Here is a patch set that introduces basic support for address decoding
> on Armada 370 and Armada XP. The aim of this basic support is
> essentially to be able to configure a window to remap the BootROM,
> which is needed to startup the secondary CPUs for the SMP support.
> As we had discussed already, the address decoding configuration is not
> described in the Device Tree, it is for now hardcoded on a per-SoC
> basis. We might later discuss how to extend this to the Device Tree.
> The patch set is relatively long, as it refactors some existing
> Dove/Kirkwood/MV78xx0/Orion code to use void __iomem pointers instead
> of unsigned long, as per the request of Arnd Bergmann and Olof
> This patch set is split in several parts:
> (1) Patches 1-4 replaces binary or operators used in register address
> definitions by plus operators. This is necessary because followup
> patches change the base addresses constants to void __iomem
> pointers, and binary or arithmetic on pointers is not
> allowed. Also, using the plus operator to add an offset to a base
> address is much more traditional. In our case, the binary or
> operator and plus operator seem equivalent, as the low-order bits
> of the base addresses that were being or'ed with an offset were
> all zero.
> (2) Patches 5-9 use the IOMEM() macro to turn the various base
> virtual addresses constants into void __iomem pointers. This
> naturally makes all derived constants (virtual addresses of
> specific registers or units) as void __iomem pointers as
> well. The patches also adjust the code to take into this
> change. It adds a few temporary "(unsigned long)" casts that are
> removed by the following patches that rework a few plat-orion
> APIs. These temporary casts are necessary to make the patch set
> properly bisectable, without having a single big patch that does
> the complete IOMEM() conversion. At the end of the patch set, the
> only (unsigned long) casts that remain are the one in the
> map_desc array definitions, and those ones are expected.
> (3) Patches 10-13 rework some plat-orion APIs so that they use void
> __iomem pointers instead of unsigned long for virtual
> addresses. Those patches also remove the now useless "(unsigned
> long)" casts added in step (2) above.
> (4) Patch 14 introduces PLAT_ORION_LEGACY, which allows the Marvell
> 370/XP platforms to be part of PLAT_ORION, and therefore re-use
> the existing address decoding code.
> (5) Patch 15 makes a small change to an address decoding structure so
> that we can define at runtime the virtual address of the
> configuration registers. This is needed as on Armada 370/XP the
> address decoding "controller" is declared in the Device Tree.
> (6) Patch 16 adds the 370/XP address decoding code itself. For now,
> it only maps the BootROM on Armada XP.
> (7) Patch 17 adds the necessary DT code to instantiate the address
> decoding "controller".
> This patch set has been:
> * Built, boot tested on Armada XP. The operation of the address
> mapping support has been tested as well.
> * Built tested only on Dove, Kirkwood, Orion5x and MV78xx0.
> Changes since v3:
> * As per the request of Olof Johansson, use void __iomem pointers
> everywhere instead of introducing more casts in the patch set. This
> change has significantly increased the patch set size, though
> (going from 5 patches in v3 to 17 patches in v4)
> Changes since v2:
> * Remove one more useless (void __iomem *) cast in the Armada 370/XP
> addr-map.c file, as noticed by Arnd Bergmann.
> Changes since v1:
> * Use void __iomem * in addr-map code. Suggested by Arnd Bergmann.
> * Add Acked-by on patches 2->5 from Grégory Clément
> Thomas Petazzoni
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
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